The problems encountered by past makers of welding devices of the type similar to that of the present invention are three-fold. The first relates to the operation of the precision welding gun, the second relates to the operation of the capacitive discharge welding base unit, and the third relates to the need for a system capable of storing, retrieving and repeating optimum welding sequences.
Regarding the precision welding gun, an example of prior art welding guns is the electroholder gun described in Italian Patent No. 957,321 (Spinnato). In the Spinnato device, a helical spring is provided and forms a central fulcrum for its arms. The tips of the arms elastically engage and act so as to close the tips of the gun. The Spinnato structure does not permit the degree of sensitivity obtained by the device described herein.
Moreover, the Spinnato patent does not disclose the quick disconnect feature of this invention, either for its sterilization, or for the substitution of gun bearing electrodes capable of satisfying different welding requirements. The gun according to the present invention satisfies this requirement, as well as other requirements.
Regarding the welding base unit, prior art devices include electric welding machines such as that disclosed and illustrated in Italian Patent No. 957,322 (Spinnato). Spinnato's machine operates on alternating current, and thus can be supplied only by network voltage, and it must be manually adapted for each individual operation so as to be tailored to specific conditions of each welding task. Prior to operation, the setting or adaptation of the device requires experimentation with a model in a test mode to ensure proper operation of the device in the real mode. Such preliminary checks are required because of possible changes in the network voltage supply and because of differences in the thickness of the materials to be welded as it is impossible to adjust the pressure of the welding gun employed with such welding devices in operation.
Prior art welding systems suffer the basic defect of poor repeatability of processes or welding sequences, thus making such systems ineffective or not useful for medical endo-oral applications. Thus, such systems need the capabilities of evaluating, permanently storing and repeating (if appropriate) welding sequences so that the welding sequences used are optimized in accordance with the type of metals and alloys used for welding, the form of the welded elements, and surface characteristics.